Therapeutic tents are commonly used to surround a bed patient to provide the patient with a conditioned air environment. In particular, children and adults in respiratory distress are often placed within transparent plastic tents for aerosol therapy. This is a more convenient means of aerosol delivery than using closed respirators and other inhalation therapy devices. Although the mist and expanding gas (often oxygen enriched) has a cooling effect, body heat of the patient soon makes the environment uncomfortably warm and humid, thus impairing the value of the therapy. It is therefore desirable to maintain the environment at a comfortable temperature and humidity while delivering aerosol for indefinite periods of time.
To condition the air, ice and ice filled heat exchangers, with and without recirculating fans, have often been used. These have several disadvantages, the most obvious being the need for replenishing the ice and removing the water.
Conventional refrigeration systems of the type including a compressor, a condensor, a heat exchanger, and a fan to move the air have been used instead of the ice cooling systems. An example of such an compressor type cooling apparatus is distributed by Ohio Medical Products of Madison, Wis. Although in many ways an improvement over ice cooling systems, a conventional compressor refrigeration system requires the usual maintenance and generates a fair amount of noise. They are also bulky, relatively expensive and difficult to clean between uses. To eliminate the noise from the fan, one version of a compressor refrigeration system uses a large condensor mounted within the tent. However, this system is bulky, difficult to set up, difficult to clean and is a relative inefficient heat exchanger.
U.S. Pat. No. 3,283,502 to Donohue discloses a thermoelectric cooler for oxygen tents. Although this design eliminates some of the problems associated with compressor refrigeration systems, the unit is still large and bulky. It also appears that the unit would be quite difficult to clean thoroughly between uses because the paths traversed by the cool air and its general physical construction.
What has been missing in the prior art is a small, lightweight, quiet, easy to clean and sterilize heat exchanger for cooling the air within a therapeutic tent.